JUNIOR CERTIFICATE EXAMINATION 1999
TECHNICAL GRAPHICS
HIGHER LEVEL CHIEF EXAMINER’S REPORT
ORDINARY LEVEL CHIEF EXAMINER’S REPORT
Chief Examiner’s Report
Table of Contents
1.HIGHER LEVEL EXAMINATION
1.1
1.2
1.3
1.4
1.5
Overview (description of examination)
Commentary on individual sections of the examination paper
Commentary on individual questions of the examination paper
Popularity of questions
Average marks awarded
2.ORDINARY LEVEL EXAMINATION
2.1
2.2
2.3
2.4
2.5
Overview (description of examination)
Commentary on individual sections of the examination paper
Commentary on individual questions of the examination paper
Popularity of questions
Average marks awarded
3.STATISTICS
3.1 Level at which candidates participated (uptake at each level)
3.2 Results achieved (Grades awarded in 1999)
3.3 School Sectors Represented
3.4 Commentary of Higher Level Statistics
3.5 Commentary on Ordinary Level Statistics
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Chief Examiner’s Report
TECHNICAL GRAPHICS
HIGHER LEVEL EXAMINATION
1.1
Overview.
•
•
•
Three hour examination
Two sections (Section A and Section B)
Total marks 400
1.2
Commentary on individual sections.
SECTION A
Section A consists of 15 short answer questions of which candidates must attempt 12.
Section A - 120 marks out of the total 400 marks.
SECTION B
Section B consists of 6 longer type questions of which the candidate must attempt 4.
Section B - 280 marks out of the total 400 marks.
1.3
Commentary on individual questions
SECTION A
Q1. (To indicate the meaning of an obtuse angle and a sector of a circle)
Answered well in the majority of cases. A number of candidates produced a drawing of
a segment rather than a sector.
Q2. (To inscribe an equilateral triangle in a given circle)
Generally well answered. In some cases an equilateral triangle was drawn smaller than
its required size.
Q3. (To demonstrate an understanding of hardware devices used in a CAD facility)
Most candidates correctly listed the mouse but were less successful in selecting the
plotter.
Q4. (Orthographic views on a square grid)
Well answered.
correctly.
In a number of cases the orthographic views were not arranged
Q5. (Perspective drawing using given vanishing points)
Reasonably well answered. A number of candidates had difficulty with the lines
required for the seat of the armchair.
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Chief Examiner’s Report
Q6. (Isometric drawing on a grid)
Candidates scored well in this question.
Q7. (Loci)
Not a popular choice and poorly answered by a number of those attempting it. Very
few candidates applied the required distance perpendicular to the line L. Guesswork
was frequent.
Q8. (Development)
The standard of answering was varied. Some candidate had difficulty in establishing
the developed length of the curved surface.
Q9. (Solids in Contact)
A common error was the use of guesswork to locate the centre of the sphere in
elevation. Many candidates showed either the normal at point “P” or the bisector of the
angle, but rarely both.
Q10. (Determining the minor axis length of an ellipse)
Standard of answering was good. Most attempts were based on the concentric circles
method. Having constructed the major circle, many candidates concluded with
guesswork.
Q11. (Sketching and Shading)
Answered poorly in most cases. Some candidates attempted to convey shadow rather
than shading the sketch as required by the question.
Q12. (Completing the elevation of a cut solid)
Poorly answered, most candidates had difficulty in completing the elevation having
projected the points from the plan.
Q13. (Area)
Approximately half the candidates attempting this question had difficulty establishing
the necessary height of the triangle. In most cases however, the 55º base angle was
correctly drawn.
Q14. (Axial symmetry)
This question was answered very well. A small number of candidates did not reflect
points perpendicularly in the line L.
Q15. (Completion of elevation, given plan and end view of a cut solid)
Answered well by the majority of candidates. In some cases the hidden detail for the
rear two edges of the solid was omitted.
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Chief Examiner’s Report
SECTION B - HIGHER LEVEL
Question 1.
Orthographic Projection
Parts (a) and (b) (elevation and plan respectively) were very well answered. Difficulties
with the auxiliary plan included an incorrect angle for the X1-Y1, not projecting at right
angles to the surface “S” in elevation and omission of hidden detail. In some cases
candidates only showed the surface “S” in the auxiliary plan. A small number of
candidates projected an auxiliary elevation of the model aeroplane.
Question 2.
Mapping / Rotation
Part (a), which involved drawing the given views, as answered exceptionally well.
Instead of the required plan, some candidates produced a view identical to the given
elevation. Others, having set-up the required plan correctly, experienced difficulty with
the semi-elliptical curves and drew semi-circles instead.
Question 3.
Isometric Projection
This question was well answered by the vast majority of candidates. Option (a), using
the axonometric axes method, proved slightly more popular than option (b), using the
isometric scale method. A small number of candidates lost marks for not showing the
construction used to locate points on the curves.
Question 4.
Solids in Contact / Surface Development
This question was generally not well answered. While the given views were well
drawn, a considerable number of candidates showed no construction for the tangential
surfaces at 60º to the horizontal plane in the end view. Attempts at the plan were poor,
with a number of lines omitted. The required points of contact were shown by very few
candidates with most having neglected to locate them in the end view. The required
surface development (of one of the hexagonal ends) was omitted or handled poorly by
most candidates.
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Chief Examiner’s Report
Question 5.
Transformation Geometry
Generally very well answered. Fixing the centre of rotation and locating all the image
points correctly, following a 120º anti-clockwise rotation gave rise to errors in only a
small number of cases.
Question 6.
Ellipse and Parabola
Generally very well answered, apart from the requirement to show clearly the
construction required to determine the position of the vertex B of the parabola and the
point of contact D between the ellipse and the base of the trophy. In the majority of
cases the horizontal tangents to the ellipse were fitted without construction. Most
candidates correctly drew both curves.
1.4
Popularity of Questions - Section B
•
The majority of candidates attempted the required four questions in this section. Quite a
small proportion (8%) attempted five questions while 1.6% attempted six questions.
•
Certain questions are more popular than others. Question 1 on Orthographic Projection,
which included an auxiliary plan, was the most popular choice followed by Question 2
which was based on a mapping / rotation. Question 4 on Solids in Contact /
Development was the least popular.
•
These finding are presented in Table 1 below and illustrated graphically in Figure 2.
Popularity of Questions (Section B - Higher Level)
Order of
Question
Popularity %
Topics
Popularity
1st
Question 1
90%
Orthographic Projection
2nd
Question 2
78%
Mapping / Rotation
rd
3
Question 5
75%
Transformation Geometry
th
4
Question 6
66%
Ellipse / Parabola
5th
Question 3
62%
Isometric Projection
6th
Question 4
27%
Solids in Contact / Development
Table 1. Popularity of Questions - Section B
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Chief Examiner’s Report
Popularity of Questions
(Section B - Higher Level)
100%
80%
60%
40%
20%
0%
Q1
Q2
Q3
Q4
Q5
Q6
Questions from Section B
Attempted by %
Figure 2. Graph showing popularity of questions - Section B.
1.5
Average marks awarded
•
The average mark awarded for Section A was 85 out of a possible 120 marks, which is
equivalent to 71%.
•
The average mark awarded for Section B was 192 out of a possible 280 marks, which is
equivalent to 69%.
•
The average total mark awarded for the paper as a whole (Section A combined with
Section B) was 277 out of a possible 400 marks. This is equivalent to 69%, a high
grade ‘C’.
An analysis of the average mark awarded for each question in Section B further highlights
variations in marks awarded to candidates. Interestingly, the questions that attracted the
highest average marks were not the most popular questions.
•
Question 3 on Isometric Projection received the highest average marks.
•
Question 4 on Solids in Contact / Development received the lowest average marks.
(This question was also least popular).
The average marks awarded for each of the questions in Section B are set out in Table 3
below and illustrated graphically in Figure 4.
(Note: Each question in Section B carried a maximum of 70 marks.)
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Chief Examiner’s Report
Average Marks Awarded (SectionB – Higher Level)
Question
Average Mark
Topics
Question 3
59
Isometric Projection
Question 5
50
Transformation Geometry
Question 6
49
Ellipse / Parabola
Question 1
48
Orthographic Projection
Question 2
47
Mapping / Rotation
Question 4
35
Solids in Contact / Development
Rank Order
1st
2nd
3rd
4th
5th
6th
Table 3. Average marks awarded per Question: Section B
Average Marks Awarded
(Section B - Higher Level)
70
60
50
40
30
20
10
0
Q1
Q2
Q3
Q4
Q5
Questions from Section B
Average Mark Awarded
Figure 4. Graph showing average marks awarded per question in Section B.
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Chief Examiner’s Report
TECHNICAL GRAPHICS
ORDINARY LEVEL EXAMINATION
2.1
Overview
•
•
•
Two and a half hour Examination.
Two sections (Section A and Section B)
Total marks 400
2.2
Commentary on individual sections.
SECTION A
Section A consists of 15 short answer type questions of which candidates must attempt 10.
Section A - 120 marks out of the total 400 marks.
SECTION B
Section B consists of 6 longer type questions of which candidates must attempt 4.
Section B - 280 marks out of the total 400 marks.
2.3
Commentary on individual questions
SECTION A
Q1. (To complete an Orthographic)
Well answered. Some candidates omitted projection lines and hidden detail lines.
Q2. (CAD commands)
Poorly answered. Knowledge of CAD commands was poor.
Q3. (Computer Devices)
Well answered. Almost 100% correct in the answers provided.
Q4. (Convert to a Rectangle, twice the given area)
Well answered.
Q5. (Ellipse)
Poorly answered. No construction lines were shown in many solutions.
Q6. (Pentagon)
Poorly answered. Many candidates guessed the shape.
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Chief Examiner’s Report
Q7. (Isometric)
Very well answered. Dimensional inaccuracies were the main errors.
Q8. (Scale)
Very well answered. Popular question.
Q9. (Area)
Very well answered and a popular question with candidates.
Q10. (Auxiliary)
Poorly attempted. Many candidates exhibited a poor understanding of auxiliary
projection.
Q11. (Isometric drawing on grid)
Very well answered. The standard of answering of this question is improving.
Q12. (Shadow)
Some candidates resorted to guesswork when determining the shadow on the vertical
plane. Otherwise, well answered.
Q13. (External Tangent to two circles)
Poorly answered. Many candidates did not know the required constructions.
Q14. (Perspective)
Well answered. Some candidates omitted the projection lines to the Vanishing Points.
Q15. (Rotation)
A popular question, errors that did occur were in the orientation of the rotated figure.
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Chief Examiner’s Report
SECTION B
Question 1.
Orthographic Projection – Oil Storage Tank
Very well answered. The placing of the end elevation on the incorrect side of the
elevation, the omission of the hidden detail and dimension lines were the most common
errors.
Question 2.
Ellipse -A Shop Display Sign
Very well answered. However, many candidates did not show clearly a method for
obtaining points on an ellipse. Most candidates had little difficulty in completing the
outline figure. However, the construction for the location of the centre of the three arcs
was seldom shown.
Question 3.
Development - A Litter Box
Very well answered. The location of the end elevation on the incorrect side of the
elevation and omission of the fold lines in the development were the main errors.
Question 4.
Pictorial Drawing using Oblique or Isometric - A Computer Game Show Award
Very well answered. Some candidates did not show the correct angle for the axes of
projection.
Question 5.
Transformation Geometry
This question was not well answered. Candidates generally had a poor understanding of
Axial Symmetry and Central Symmetry.
Question 6.
Plane Figures - A Child’s Toy
This question was not well answered. Many candidates omitted the necessary
constructions required to locate the points of contact to each of the circles and to the
centres for each of the arcs. Points of contact were frequently omitted.
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Chief Examiner’s Report
2.4. Popularity of Questions - Section B
•
•
The vast majority of candidates attempted the required four questions in this section.
Quite a small proportion (3.4%) attempted five questions while 0.5% attempted six
questions.
Some questions are more popular than others. Question 3 on Development, was the
most popular choice followed by Question 2 which examined the Ellipse. Question 5
on Transformation Geometry was the least popular.
The results are presented in Table1 below and illustrated graphically in Figure 2.
Popularity of Questions (Section B - Ordinary Level)
Order
Question
Popularity %
of Popularity
1st
Question 3
82%
2nd
Question 2
76%
3rd
Question 1
68%
4th
Question 4
54%
5th
Question 6
53%
6th
Question 5
29%
Table 1. Popularity of questions in Section B.
Topics
Developments
Ellipse
Orthographic Projection
Pictorial Drawing
Plane Figures
Transformation Geometry
Popularity of Questions
(Section B - Ordinary Level)
100%
80%
60%
40%
20%
0%
Q1
Q2
Q3
Q4
Q5
Questions from Section B
Attempted by %
Figure 2: Graph showing popularity of Questions in Section B.
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Chief Examiner’s Report
2.5
Average marks awarded
•
The average mark awarded for Section A was 83, which is equivalent to 69.2%.
•
The average mark awarded for Section B was 188, which is equivalent to 67.4%.
•
The average total mark awarded for the paper as a whole (Section A combined with
Section B) was 271 out of a possible 400 marks. This is equivalent to 67.8%, a high
grade ‘C’.
An analysis of the average mark awarded for each question in Section B further highlights
variations in performance of candidates. Interestingly, the questions that attracted the highest
average marks were not the most popular questions.
•
•
Question 4 on Pictorial Projection received the highest average mark, followed by
Question 5 on Transformation Geometry.
Question 3 on Development received the lowest average mark.
The average marks awarded for each question in Section B are set out in Table 3 below and
illustrated graphically in Figure 4.
(Note: Each question in Section B carried a maximum of 70 marks.)
Average Marks Awarded (SectionB – Ordinary Level)
Rank Order
Question
Average Mark
st
1
Question 3
50
nd
2
Question 5
48
2nd
Question 6
48
2nd
Question 1
48
rd
3
Question 2
45
4th
Question 4
44
Table 3. Average marks awarded per question in Section B.
Topics
Pictorial Drawing
Orthographic Projection
Ellipse
Transformation Geometry
Plane Figures
Development
Average Marks Awarded
(Section B - Ordinary Level)
70
60
50
40
30
20
10
0
Q1
Q2
Q3
Q4
Q5
Q6
Questions from Section B
Average Mark Awarded
Figure 4. Graph showing average marks awarded per question in Section B.
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Chief Examiner’s Report
3.
3.1
EXAMINATION STATISTICS
Level at which candidates participated (uptake at each levels)
Table1 below shows the uptake at each level since 1996.
Level at which Candidates Participated
% Higher
Total Number of
Technical Graphics
Candidates
18,765
47.4%
1996
17,393
52.5%
1997
16,972
53.0%
1998
16,128
51.9%
1999
Table 1: Uptake of Technical Graphics.
% Ordinary
Year
3.2
52.6%
47.5%
47.0%
48.1%
Distribution of Grades – 1999.
Table 2 below sets out the grades awarded at Higher and Ordinary Levels for 1999. This data
is illustrated graphically in Figure 3.
Distribution of Grades
Higher
Ordinary
Number of
%
Number of
Candidates
Candidates
1,249
14.9%
943
2,849
34.0%
2,489
2,674
31.9%
1,877
1,324
15.8%
1,434
247
2.9 %
594
34
0.4%
374
5
0.1%
55
8,382
100%
7,766
Grade
A
B
C
D
E
F
N/G
Total
Table 2: Distribution of Grades
%
12.1%
32.0%
24.2%
18.5%
7.6%
4.8%
0.7%
100%
Distribution of Grades 1999
Technical Graphics - Higher Level and Ordinary Level
40%
30%
20%
10%
0%
A
B
C
D
E
F
Grades Awarded
Percentages at Higher Level
Percentages at Ordinary Level
Figure 3. Graph showing distribution of grades at Ordinary and Higher Level.
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Chief Examiner’s Report
3.3 Provision of Technical Graphics by school type
Schools by Sector taking Technical Graphics
Secondary
230
Vocational
213
Community
64
Comprehensive
14
3.4 Commentary on Higher Level Statistics
When the Junior Certificate Technical Graphics syllabus was introduced into the schools it
was envisaged that the ratio of Higher Level to Ordinary Level candidates would be
approximately two-thirds to one-third. This year slightly under 52% of the candidates opted
for Higher Level. A total of 80.6% of the Higher Level candidates achieved an A, B or C
grade. Many candidates who could attempt the Higher Level are opting to sit the examination
at Ordinary Level. A total of 3.9% of candidates did not achieve a D grade at Higher Level.
3.5 Commentary on Ordinary Level Statistics
A total of 13.0% of candidates did not achieve a D grade at Ordinary Level. Many of these
candidates did not attempt the required number of questions and consequently were
disadvantaged.
The number of questions attempted by candidates in Section B is as follows:
•
15.5% attempted 3 questions out of the 4 required in Section B.
•
6.1% attempted 2 questions.
•
3.4% attempted 1 question.
•
0.3% attempted 0 questions.
Conclusion
A total of 12.3% of candidates were awarded an A Grade at Ordinary Level. It would appear
that a significant number of candidates, who take the examination at Ordinary Level, are
capable of taking the examination at the Higher Level. It is hoped that candidates will give
more consideration to the level at which they wish to present for examination and that
teachers will encourage candidates to take the Higher Level where appropriate.
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